They say in that blogpost that they do separate transactional and bulk email: > Q: How will you maintain high deliverability for transactional email? > A: Sep

They say in that blogpost that they do separate transactional and bulk email: > Q: How will you maintain high deliverability for transactional email? > A: Separating transactional traffic from other types of email using different sending IPs and From domains is a longstanding best practice for ensuring optimal deliverability. ... > That means transactional and broadcast traffic never intersect in Postmark, including IP ranges. https://postmarkapp.com/blog/api-bulk-the-final-frontier#how-will-you-maintain-high-deliverability-for-transactional-email https://postmarkapp.com/blog/api-bulk-the-final-frontier#how...